My dear wife had this dream...She was wearing a white beautiful wedding dress in a church setting and everyone was seated and in walked another friend IRL [she is her friend who occasionally comes to church ] wearing the same cut wedding dress but hers looking dirty and she was looking extremely short en petit but IRL [almost as tall as my wife]. So my wife demanded where she was coming from looking like that because she [my wife] was coming from a party and suddenly her parents including herself began to laugh aloud.

In real life, does anyone stand out to your wife as imitating her in some area? The imitation shouldn't be flattery/positive.

The dirty dress may represent unrepented sin.

The shortness of the person in the dream could be to show you that the friend isn't literal - that she represents someone else. If she is literal, then her height may show you how she feels (small or inadequate).

The laughter at the end could show that this person isn't taking their behavior very seriously.

Did your wife perahps see a picture of the church which is the bride of Christ? She saw what it's supposed to be; her clean white beautiful dress (a church without spot or wrinkle or any such blemish). Yet, the bride's dress is dirty and In need of cleaning and short as in coming up short. This bride cannot meet the bridegroom in this state; not ready and not taking the matter seriously. If you think of the parable of the 10 virgins; 5 were wise and 5 were foolish. In your wife's dream, it appears that one bride was ready but the other was not.